Choose the correct statement

Options

A. Growth in multicellular organisms cannot take place in in vitro culture.
B. Growth by cell division in unicellular organisms can be observed in in vivo culture.
C. Growth by cell division in unicellular organisms can be observed in in vitro culture.
D. Growth by cell division in unicellular organisms cannot be observed by any method.

Answer

To solve the question "Choose the correct statement," we will analyze each option provided and determine which one is correct based on the concepts of in vitro and in vivo growth.

### Step-by-Step Solution:

1. **Understand the Terms:**
- **In Vitro:** This refers to processes or reactions occurring in a controlled environment outside of a living organism, such as in a test tube or culture dish.
- **In Vivo:** This refers to processes occurring within a living organism.

2. **Analyze Each Option:**
- **Option 1:** "Growth in multicellular organism cannot take place in vitro culture."
- This statement is incorrect because multicellular organisms can indeed be cultured in vitro, although the growth may not be as effective as in vivo.

- **Option 2:** "Growth by cell division in unicellular organism can be observed in vivo culture."
- This statement is misleading. While unicellular organisms can grow in vivo, the statement does not highlight the in vitro aspect which is also applicable.

- **Option 3:** "Growth by cell division in unicellular organism can be observed in vitro culture."
- This statement is correct. Unicellular organisms, such as bacteria and yeast, can grow and divide in vitro under controlled conditions.

- **Option 4:** "Growth of cell division in unicellular or multicellular cannot be observed by any method."
- This statement is incorrect as growth can be observed through various methods, both in vitro and in vivo.

3. **Conclusion:**
- After analyzing all the options, the correct statement is **Option 3:** "Growth by cell division in unicellular organism can be observed in vitro culture."

### Final Answer:
The correct statement is: **Growth by cell division in unicellular organism can be observed in vitro culture.**